LONDON — Seven men have been arrested on suspicion of terrorist offenses in Britain after a routine vehicle search in northern England turned up firearms and weapons, police said Friday.
The arrests, which took place earlier this week, were announced one day after officers in London detained six other terrorism suspects in early-morning sweeps, including one on a home close to London’s Olympic Park.
Police said the 13 arrests in recent days did not involve threats to the Olympics scheduled to begin in three weeks, but the counter-terror sweeps — and a false alarm Thursday that involved a bus filled with passengers — have raised anxiety in advance of the games.
The arrests came as transport officials established special ‘‘games lanes’’ on key London roads that will be used by Olympic athletes, officials, and VIPs, adding to the sense that the start of the long-awaited Olympics is near.
Police on Friday said there was nothing to suggest that the newly announced arrests were tied to London raids a day earlier. They said the arrests came as a car was stopped on the M1 highway in South Yorkshire on June 30 and impounded for not having insurance.
Two unloaded, nonautomatic guns and a small amount of ammunition were later found hidden in the vehicle along with ‘‘offensive weapons and other material,’’ which prompted police to trace and arrest the driver, passenger, and other suspects, according to West Midlands Police.
Prime Minister David Cameron’s spokesman Steve Field said there was no sense of alarm at the spate of arrests near the Summer Games start.
ASSOCIATED PRESS